The Minnesota State Patrol is looking for what it is calling a "semi of interest" in connection with a rollover crash that killed two teenage brothers from Moorhead, Minn. last summer.

On Wednesday, the patrol released photos of a semitrailer truck that was believed to be in the vicinity of the June 23, 2015 crash on Interstate 94 near milepost 69, east of Fergus Falls in northwestern Minnesota.

Investigators have been trying to piece together exactly what happened that caused an eastbound pickup truck driven by Zachary Kvalvog, 18, to go off the road around 9:10 a.m. A state patrol incident report said Kvalvog hit the shoulder, over corrected, rolled into the median and then came to rest in the westbound lanes. Kvalvog, 18, and his brother, Connor, 14, were killed. Two other teens riding in the vehicle were injured. The four teens had been headed to a basketball tournament in Wisconsin.

"A semi may be a factor, maybe cutting them off," said Sgt. Jesse Grabow of the State Patrol. "This was not a hit-and-run. It is a semi of interest."

The semi is described as a late-'80s to mid-90s Kenworth tractor, Model T600 to T800, with an Aerodyne sleeper and dark blue cab. It has what appears to be a KW T680 Grille Guard or something similar, the patrol said.

Photographs also show one radiator, or grill bar, running vertically from the hood ornament straight down. Its license plate from an unknown state has a sequence of numbers of either 024 or 025, most likely at the end of the plate sequence, the patrol said.

Dennis McGrath, Star Tribune
This semi may have played a role in a fatal accident on I-94 near Fergus Falls in June 2015.

The semi and its all-white trailer, which has no visible identifying marks on it, was determined to be near the crash site, Grabow said. State Patrol investigators analyzed GPS units of other semitrailers as they passed through the Red River weigh station, which is just inside the Minnesota-North Dakota border in Moorhead. The patrol applied time-distance analysis, reviewed video from a responding State Patrol squad and enhanced photographs taken at the Red River station to determine the semi in question.

Grabow said information has been scant, and he's hoping that by releasing photos it might spark the memory of somebody who might have seen something that could lead police to the truck or its driver.

"We have not had a lot of information," Grabow said. "We'll take any information to move forward. Anything could help."

Anybody with information about a vehicle matching this description is asked to call Sgt. Rod Eischens at 1-218-846-8244 or e-mail Rod.Eischens@state.mn.us.

Tim Harlow • 612-673-7768